The invention relates to solar heated buildings, and more particularly to solar heated buildings of the type having a frame, and inner and outer walls supported on the frame, the walls defining passages for the flow of a heat transfer medium.
Reference may be made to German DE-OS No. 2,522,791 and Suddeutsche Zeitung No. 104, May 6, 1974, p. 7, "Solar Energy Use: Small Hope for Europe" showing buildings of this type in use as greenhouses, the inner and outer walls of the buildings being made of thermosetting plastic or glass and the heat transfer medium being a fluid such as water circulated in the passages between the walls. Ventilation means may be incorporated into the buildings, usually at the sides thereof, for enabling air to flow into and out of the buildings for ventilating and for regulating the temperature of the interior thereof. A disadvantage of the ventilation means is that when the ventilation means is opened in winter, cold air can flow directly into the buildings. Thus when such a building is used as a greenhouse, the cold air flows onto the plants and damages them. Similarly, if the building were used as shelter for a swimming pool, the cold air would flow directly into the building, thereby making at least some parts of the building uncomfortable. In addition, the ventilation means often comprises a long sheet of plastic material wound on a rotatably mounted shaft, the sheet being unwound and extending across openings in the buildings for blocking the flow of air. Problems with such ventilation means include its high heat loss and its inability to regulate air flow through each opening independently of that through the other openings.